1. Field of the Invention
The present invention relates to a head cap which covers or caps an ink-ejection surface of a liquid-droplets ejection head configured to eject liquid droplets, a liquid-droplets-ejection-head recovering mechanism for recovering a liquid-droplets-ejection property of the liquid-droplets ejection head, and a liquid-droplets ejection printer including the liquid-droplets ejection head.
2. Description of the Related Art
In an ink-jet printer, there is known a technique that an ink-ejection surface of a head is sealed by a cap when recording is not performed, thereby preventing drying of nozzles opened in the ink-ejection surface. Where the ink-ejection surface is sealed by the cap, when the printer or only a head thereof is stored for a relatively long time or transported by, e.g., aircraft, a pressure difference between an inside of the cap and air may become relatively large by a pressure fluctuation of ambient atmosphere, and thus a liquid such as an ink and a storage liquid may leak from the nozzles. In order to prevent this, there is proposed, in Patent Document 1 (Japanese Patent Application Publication No. 2003-089210), to form an air communication channel having an appropriate resistance (channel resistance) to a flow of the air in the channel in order to communicate the inside of the cap and the air and to prevent the nozzles from drying.
In this air communicating channel, in accordance with decrease in the channel resistance thereof, an effect for preventing the drying of the nozzles by the cap is reduced. In the above-described air communicating channel, a length thereof is secured for obtaining the channel resistance. For example, in Patent Document 1, an air-communication groove extending while bending is formed in an upper surface of a cap holder holding the cap, and a back surface of the cap formed by a rubber elastic body and the upper surface of the cap holder closely contact with each other by a pressure during capping, thereby forming the air communicating channel.